Probably need to allow customers to see closed tickets. It's a setting in the customer's detail.

From: otrs-bounces@otrs.org [mailto:otrs-bounces@otrs.org] On Behalf Of Hien HUYNH HUU
Sent: Monday, September 14, 2009 3:47 AM
To: otrs@otrs.org
Subject: [otrs] Merge tickets with Customer

Dear all,

    I used merge for new ticket with the old ticket. But the customer can’t see old ticket . I want to let new customer can see their answer in the old ticket when their ticket is merged. Please help me to solve this issue .   Best regards,

    Huu Hien